title: Levonorgestrel and estradiol release from an improved contraceptive vaginal ring.
mesh_terms: D003274:Contraceptive Devices, Female; D003692:Delayed-Action Preparations; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D016912:Levonorgestrel; D009644:Norgestrel / Q000378:metabolism*; D014621:Vagina
chemical_list: D003692:Delayed-Action Preparations; D009644:Norgestrel; D004958:Estradiol; D016912:Levonorgestrel